linux-kernel - Re: [PATCH] Fix __d_path for lazy unmounts

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <4B82BDDD.9020407@canonical.com>
Date:	Mon, 22 Feb 2010 09:24:45 -0800
From:	John Johansen <john.johansen@...onical.com>
To:	john.johansen@...onical.com
CC:	linux-kernel@...r.kernel.org, linux-fsdevel@...r.kernel.org
Subject: Re: [PATCH] Fix __d_path for lazy unmounts

john.johansen@...onical.com wrote:
> From: John Johansen <john.johansen@...onical.com>
> 
> When __d_path() hits a lazily unmounted mount point, it tries to prepend
> the name of the lazily unmounted dentry to the path name.  It gets this wrong,
> and also overwrites the slash that separates the name from the following
> pathname component. This patch fixes that; if a process was in directory
> /foo/bar and /foo got lazily unmounted, the old result was ``foobar'' (note the
> missing slash), while the new result with this patch is ``/foo/bar''.
> 
It seems I left out the basic test for this.  From a shell you can do

> mkdir /tmp/foo
> sudo mount --bind /home/jj /tmp/foo   #substitute /home/jj as you wish
> cd /tmp/foo/bar       # assumes /home/jj/bar exists
> /bin/pwd
/tmp/foo/bar
> sudo umount -l /tmp/foo
> /bin/pwd
jjbar
> > cd ..
> > /bin/pwd
jj


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/